James tomkey



(No Model.)

J. TOMNEY,

BURGLAR ALARM. No. 343,868. Patented June 15, 1886.

g o g 'E N. FETERS, Plush-Lithographer. wasmn mn, D. C.

UNITED STATES PATENr FFICE.

JAMES TOMNEY, OF NEW YORK, N. Y.

BU RGLAR-ALARM.

SPECIFICATION forming part of Letters Patent No. 343,868, dated June 15,1886. Application filed December 3, 1885. Serial No. 184,600. (Nomodel.)

To all whom it may concern:

Be it known that I, JAMES TOMNEY, of New York, in the county and Stateof New York, have invented a new and useful Improvement inBurglar-Alarms, of which the following is a specification.

According to an improvement in electrical burglar-alarms which I havepreviously made and patented, the resistance in the circuit is from timeto time varied to frustrate the efforts of burglars who may haveobtained knowledge of the amount of resistance existing in the circuitat any particular time. 1

The object of my present improvement is to cause a burglar-alarm torecord the number of changes which are made in the resistance of itscircuit.

I will describe a burglar-alarm embodying my present improvement, andthen point out the features of the improvement the claims.

In the accompanying drawings, Figure 1 is a diagrammatic view of aburglar-alarm embodying the improvement. The burglar-alarm is one of thekind which comprises a circuit extending through the house or place ofbusiness or safe to be guarded, and extends thence to an office, wheredevices are employed to indicate to watchmen stationed there any effortwhich may be made toward effecting an entrance to the guarded premises.Ihave indicated that portion of Fig. 1 which is intended to illustratethe house or place of business guarded by marking it with the wordsGuarded Structure, and the portion which is designed to represent theoffice where watchmen are kept by marking the same with the word Office.Fig. 2 of the drawings is a side view of a resistance-changing device.

A A designate electric batteries located in the office where watchmenare kept. Wires B B" connect them with earth-plates 0 O and other wires,B B, connect them with metallic contact-pieces B B, with which ametallic switch-arm, B, operates. A wire, 13, extends from theswitch-arm B to one of two coils comprised in a galvanometer, D. Thesetwo coils are connected together by an intermediate wire. A wire, B,extends from the other coil of the galvanometer and from the office tothe guarded structure. In the guarded structure this wire B is connectedwith the coils of an electro-magnet, E, of a recording device. A wire, Bextends from the electro-magnet E to an electro-magnet, F, of aresistance-changing device. ance-changing device is in electricalcommunication with the ground, as I shall hereinafter describe more indetail.

The recording device, of which the electromagnet E forms a part,comprises a timepiece, E, operatedin any suitable manneras, forinstance, by a spring or weight, and havinga revolving dial-plate. Thedialplate has detachably secured to it a dial made, preferably, of paperor other cheap material, and marked with numbers indicative of hours ofthe day. The armature E of the electro-magnet E is free to vibrate, asusual. It will normally be held away from the electro-magnet by a springin a well-known manner. It carries a stylus, pencil, or other marker, E,which extends over the dial of the time-piece E, without, however,acting on the latter while the armature occupies its normal position.When the electro-magnet is energized sufficiently to attract itsarmature, the marker will be caused to impinge upon the dial of thetimepiece, and the proximity of the mark made by the marker to one ofthe numbers indicative of hours upon the dial will indicate and recordthe hour at which the mark was made.

The electro-magnet F of the resistancechanging device has a vibratoryarmature, F, which is normally held away from the electromagnet by aspring. This armature is mounted upon a lever having a section ofinsulating material, provided with a pawl, F, that operates inconjunction with a metallic ratchet wheel, F affixed to a spool, F. Thespool F is supported by metal journals so as to be free to rot-ate. Thespool F has several convolutions or layers of wire wound upon it. Oneend of this wire is in electrical communication with the ratchet-wheel Fand consequently with the adjacent metallic journal of the spool. Thewire wound upon the spool is looped at the end of these several layersor convolutions, and these loops are connected to metal plates f, thatare affixed to a wheel, F of '100 insulating material,that is secured tothe spool. The outer end of the wire on the spool is also Thisresistconnected to a plate, f, on the wheel F 1 arm 13 is only left uponthe contact-piece 'B spring-finger, F, impinges upon the wheel F andmakes electrical contact with the plates f thereof, one at a time. Thespring-finger F is connected with the electro-magnet F by a wire, B. Themetallic journal of the spool F, which is adjacent to the ratchet-wheelF is connected by a wire, B to a binding-post, and this binding-post isconnected by a wire, 13, with an earth-plate, O

Whenever the switch-arm B is in contact with the contact-piece B thebattery A supplies an electric current to the burglar-alarm circuit. Thecurrent from this battery is not sufficiently powerful to cause theelectro-magnet E of the recording device to attract its armature, or tocause the electro-magnet F of the resistance device to attract itsarmature. Whenever the watchman or attendant at the office desires toeffect a change of the resistance in the burglar-alarm circuit at theguarded structure, he moves the switcharm B over the contact-piece B.Then the battery A is put into communication with the burglar-- alarmcircuit. This battery A supplies a current which energizes theelectro-magnet E of the recording device and the electro-magnet F of theresistancechanging device sufficiently to cause them to attract theirarmatures. Thereupon the stylus will make a mark upon the dial of thetime-piece E, and the pawl F will rotate the ratchet-wheel F spool F,and wheel F so that a different contact piece or platefof the latterwill be shifted into contact-with the spring-finger F. As beforeexplained, this Will vary the amount of resistance-Wire 0f the spool Fwhich is introduced into the burglar-alarm circuit. Theswitchmornentarily. It will be understood that from time to time theresistance is thus changed. A record will be made to that effect uponthe dial. The needle of the galvanometer B is free to vibrate betweentwo adjustable contact-pieces, G G. A wire, I, extends from the needleto a battery, I, a wire, 1 extends from the battery I to theelectro-magnet of an electric magnetic bell, I and a wire, 1*, extendsfrom the latter and has branch connections wit-h the adjustablecontact-pieces G G When the resistance is changed by the rotation of thespool F and wheel IF, the attendant or watchman at the office will needt readjust the contact-pieces GG v Whenever the needle of thegalvanometcr touches either of the contact-pieces G G theelectro-magnetic bell will ring an alarm.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In' an electric burglaralarm, the combination, with a main circuit,of a resistance changing device, and a recording device for permanentlyrecording changes in resistance, substantially as specified.

2. In an electric burglar-alarm, the combination of a main circuit, twobatteries of different potentials, a switch whereby either battery maybe connected with the circuit, an electromagnetic resistance-changingdevice in the circuit, and an electromagnetic recording device also inthe circuit, substantially as specified.

J AS. TOMNEY. Witnesses:

EDWIN H. BROWN, DANIEp H. DRIscoLL.

